Pictures taken with the ever ready faithful D300, my every day camera, which provides very good reach with the Sigma. After a few months use of the Nikon 500 mm vr, it seems to me that in good light, the Sigma 150-500 holds its own against the Nikon. The latter is, of course a prime, gives crispier shots in good and poor light, has a longer reach for small birds, but the Sigma, which costs 7 times less, does a good job at up to 20 meters (60feet)and is MUCH easier to handle.